No. IX. ECHINODERMATA. 277 



arm-joints in this individual being exactly 2 millims. In 

 addition to the above, variations occur in the contour of the 

 mouth-shields, and in the larger examples considerable irregu- 

 larity is also found in the number and position of the mouth- 

 papillae. Amongst this collection are several specimens 

 having a very decidedly pentagonal form of disk. 



In our opinion, none of the above variations can be 

 regarded as of greater morphological significance than growth- 

 phases, or at most individual variations only. The largest 

 specimen obtained was 11 millims. in disk-diameter. 



Ophiopholis bellis (Linck), Lyman. 



Coll. Feilden : lat. 65° N., 26 miles from Greenland coast, 

 30 fms. 



Amphiura Holbolli, Liitken. 1 



Coll. Feilden: Franklin Pierce Bay, 15 fms., bottom- 

 temperature 29°*5 F. 



An Amphiura with disk lobed ; radial shields long and 

 narrow ; mouth-shields rounded ; side mouth-shields large, 

 subtriangular, with the sides re-entering and angles rounded. 

 Three pairs of mouth-papillae, the middle ones placed higher 

 than the others. Under arm-plates pentagonal. One ten- 

 tacle-scale rounded ; arm-spines 3-4. 



Only a single specimen of Amphiura was taken ; and 

 this, although it differs slightly from the type form in the 

 relative measurements of certain points of detail, we have 

 little hesitation in assigning to Dr. Liitken's species, the 

 variations, in our opinion, not being of greater importance 

 than such as we should regard as dependent on locality and 

 conditions of life. 



The arms are less broad, and take their origin in a more 



1 So much confusion has arisen in consequence of uncertainty as to the 

 identity of the original application of the appellation O. Sundevalli, that 

 we prefer to retain Dr. Liitken's name, despite the example of certain 

 recent writers to the contrary. 



